idea for getting more air to stock intake
idea for getting more air to stock intake
Now before you blast me too badly just check out what I did and I think it makes perfect sense.
I had recently re-installed my stock intake and love the way it pulls nicer from a stop, but didn't like the way it falls flat after that.
I've looked at all kinds of posts about this nonsense and saw the graphs on stock vs. cai and saw what little difference their is overall, but it's a definite and obvious thing the way it doesn't pull hard enough, too me it just seemed to not be getting enough air.
So I popped the hood and studied the inlet and hood design, then closed it to the first click of the latch and then looked at it. The damn hood pretty much completely blocks off air going into the inlet so how could it possibly get enough air when it requires "more".
Ding! (that was the light bulb going on in my head) why not push some air up to the inlet via a different but not obvious way...but cheaply.
Here was my idea...now nevermind the crafty-ness of the work as this was all just a trial to see if my idea made any viable results...well it did.
You can definitely feel the better pull from the mid range and up, and best of all it was relatively easy and cheap.
I wanted to make a plate that would route air up to the intake from the front but not be obvious or ugly about it, the best route was from the smaller upper grille (i have a '96), I looked behind the grille and saw that their was a logical route to use up to the intake inlet on the right side, I just had to shape a plate the right way as too get around the hood latch and not cut my stupid finger every time I reached for it, but still force air up to the inlet.
I got a piece of paper and folded it around a bit to get my rough idea, then transferred it to cardboard where I taped together my basic model. Once I got the right layout I cut the tape holding the sides and folded the design out flat onto a thin and bendable/cuttable sheet of aluminum and drew some fold lines with a marker where I needed to fold the sides, bottom, and top.
Here is a pic. of this idea, it's basically a "ram air" set up as it basically takes air and shoves it up to the intake.
Here you can see I just utilized the stock screws to hold it on the lower end and then just used the fasteners for the plastic inlet to hold the scoop in place on the top and made the scoop with enough extra length to go over the top of the radiator support and then bend the metal around the back to help hold it solidly in place.
This left one thing to do. If you look at the hood when it's open to only one click of the latch you can see just how much the hood blocks the air.
I needed to shape the hood to allow the air from the scoop to pass and be guided into the air inlet.
I know it needs to be cleaned up and looks awfully rough, but it was a test bed and I didn't care since nobody was going to see it unless I pointed it out.
I used some tin snips and cut a line across and then two vertical cuts, one on each side, then used a hammer to knock the metal in and form it better to help guide the air.
Like I said, this is pretty rough, first round stuff. I'll be throwing a little body putty on their and cleaning it up later, this was just to do the basics and spray over it to keep it from rusting.
Here you can see the formed hood over top of the scoop, the view makes it look a little out of whack, but it lines up.
I know this is a little unorthodox perhaps, but it just seemed to make sense and after doing a couple different searches I didn't come up with anything that was like this, I saw hybrids and hacked up boxes, but that seemed to me like any air from inside the engine bay would still be warm and if you were getting any air from the inlet pipe it was going right out the big hole instead of forcing it's way up through the filter to the throttle body.
Now some of you may have concerns about blocking off half the grille, I can tell you that I have not seen the temperature needle budge one bit as the radiator is fed air from the massive hole we have in our front bumper alot more than this small grille up top.
Water may also be an issue, as in "rain". I drove it home for 2 1/2 hours from my girlfriends house to work, in a heavy rain, and checked it when I got back home and under the carport.
Their was a little bit of water streaking at the top of the scoop, so I pulled the plug i installed (at the port where the elbow used to go down under the battery) and it was totally dry. I then opened up the filter box and checked down in the bottom of the box, under the filter, again...totally dry.
Let me know what you guys think....I know you will anyway.
Like it or don't...it's their and it works. I've noted a nice pull all the way 'til it cuts out at the limiter now, it definitely didn't pull this nice before and seems to have done the trick nicely.
Best part, I painted it black and you can't even see it from the front with the hood closed and theirs no loud intake noise, just smooth usable power.
I had recently re-installed my stock intake and love the way it pulls nicer from a stop, but didn't like the way it falls flat after that.
I've looked at all kinds of posts about this nonsense and saw the graphs on stock vs. cai and saw what little difference their is overall, but it's a definite and obvious thing the way it doesn't pull hard enough, too me it just seemed to not be getting enough air.
So I popped the hood and studied the inlet and hood design, then closed it to the first click of the latch and then looked at it. The damn hood pretty much completely blocks off air going into the inlet so how could it possibly get enough air when it requires "more".
Ding! (that was the light bulb going on in my head) why not push some air up to the inlet via a different but not obvious way...but cheaply.
Here was my idea...now nevermind the crafty-ness of the work as this was all just a trial to see if my idea made any viable results...well it did.
You can definitely feel the better pull from the mid range and up, and best of all it was relatively easy and cheap.
I wanted to make a plate that would route air up to the intake from the front but not be obvious or ugly about it, the best route was from the smaller upper grille (i have a '96), I looked behind the grille and saw that their was a logical route to use up to the intake inlet on the right side, I just had to shape a plate the right way as too get around the hood latch and not cut my stupid finger every time I reached for it, but still force air up to the inlet.
I got a piece of paper and folded it around a bit to get my rough idea, then transferred it to cardboard where I taped together my basic model. Once I got the right layout I cut the tape holding the sides and folded the design out flat onto a thin and bendable/cuttable sheet of aluminum and drew some fold lines with a marker where I needed to fold the sides, bottom, and top.
Here is a pic. of this idea, it's basically a "ram air" set up as it basically takes air and shoves it up to the intake.
Here you can see I just utilized the stock screws to hold it on the lower end and then just used the fasteners for the plastic inlet to hold the scoop in place on the top and made the scoop with enough extra length to go over the top of the radiator support and then bend the metal around the back to help hold it solidly in place.
This left one thing to do. If you look at the hood when it's open to only one click of the latch you can see just how much the hood blocks the air.
I needed to shape the hood to allow the air from the scoop to pass and be guided into the air inlet.
I know it needs to be cleaned up and looks awfully rough, but it was a test bed and I didn't care since nobody was going to see it unless I pointed it out.
I used some tin snips and cut a line across and then two vertical cuts, one on each side, then used a hammer to knock the metal in and form it better to help guide the air.
Like I said, this is pretty rough, first round stuff. I'll be throwing a little body putty on their and cleaning it up later, this was just to do the basics and spray over it to keep it from rusting.
Here you can see the formed hood over top of the scoop, the view makes it look a little out of whack, but it lines up.
I know this is a little unorthodox perhaps, but it just seemed to make sense and after doing a couple different searches I didn't come up with anything that was like this, I saw hybrids and hacked up boxes, but that seemed to me like any air from inside the engine bay would still be warm and if you were getting any air from the inlet pipe it was going right out the big hole instead of forcing it's way up through the filter to the throttle body.
Now some of you may have concerns about blocking off half the grille, I can tell you that I have not seen the temperature needle budge one bit as the radiator is fed air from the massive hole we have in our front bumper alot more than this small grille up top.
Water may also be an issue, as in "rain". I drove it home for 2 1/2 hours from my girlfriends house to work, in a heavy rain, and checked it when I got back home and under the carport.
Their was a little bit of water streaking at the top of the scoop, so I pulled the plug i installed (at the port where the elbow used to go down under the battery) and it was totally dry. I then opened up the filter box and checked down in the bottom of the box, under the filter, again...totally dry.
Let me know what you guys think....I know you will anyway.
Like it or don't...it's their and it works. I've noted a nice pull all the way 'til it cuts out at the limiter now, it definitely didn't pull this nice before and seems to have done the trick nicely.
Best part, I painted it black and you can't even see it from the front with the hood closed and theirs no loud intake noise, just smooth usable power.
Last edited by back2basics; Oct 12, 2012 at 07:08 PM.
LOL!! See, that's what happens when you only search under "4th gen" in the advanced search.
As stated though, the GAB allows warmer air from the engine bay to get sucked in...not what I was looking for.
Do you have a link by any chance? I wouldn't mind seeing the difference between his idea and mine, hell..maybe they are really similar.
Well, either way. I gotta call it for tonight, got work in the morning and I won't be back on here all weekend...headin' outta town!
As stated though, the GAB allows warmer air from the engine bay to get sucked in...not what I was looking for.
Do you have a link by any chance? I wouldn't mind seeing the difference between his idea and mine, hell..maybe they are really similar.
Well, either way. I gotta call it for tonight, got work in the morning and I won't be back on here all weekend...headin' outta town!
Last edited by back2basics; Oct 12, 2012 at 08:07 PM.
Senior Member
Joined: Sep 2010
Posts: 10,344
From: Jacksonville, FL
Here is a link to his http://forums.maxima.org/5th-generat...01-maxima.html
The major difference between them is that the 4th gen has it's intake blocked by the hood design, which I shaped to allow that cold air to get in better, he didn't do that, but maybe the 5th gen. doesn't have the hood blocking the inlet like ours does...never saw, don't know.
Other than that the only thing different is the way I guided the air up to the full width of the inlet (doubt that matters at all) and that I shaped it up over the radiator support, none of that really matters as much as getting that metal out of the way.
The major difference between them is that the 4th gen has it's intake blocked by the hood design, which I shaped to allow that cold air to get in better, he didn't do that, but maybe the 5th gen. doesn't have the hood blocking the inlet like ours does...never saw, don't know.
Other than that the only thing different is the way I guided the air up to the full width of the inlet (doubt that matters at all) and that I shaped it up over the radiator support, none of that really matters as much as getting that metal out of the way.
Dangit T_Behr, you posted it up while I was busy reading the darn thing...thanks for finding though.
Junior Member
Joined: Oct 2012
Posts: 67
From: New York
You cant "ram" air into the scoop all the way to the intake manifold... even if you are driving 100mph and air is moving into the scoop, the air has to make five 90º turns, which will kill the "ram" effect. Stock air box has no gains over any aftermarket setup
I did research on here and saw a post from years ago where they did a dyno test between the CAI and stock and the stock did better "overall" and especially on the low end but not as much on the high end, all I'm giving is a different way to direct that cold air up the the stock inlet for those people that like the advantages that the stock intake gives but would like it to breathe just a little better on the high end.
Nobody said it was better than anything...it's just an idea that I tried.
Junior Member
Joined: Oct 2012
Posts: 67
From: New York
Ive owned every intake imaginable and dynoed them all. Injen and the FWI had great low to mid gains, and slight high end gains. SRI had slight gains all around.
In actual driving conditions, Injen and FWI feel the same. More power on cold days, not so much on blazing hot days.
Actually the opposite is truer.
No aftermarket setup has any gains over stock air box. Unless your cammed and tuned, the stock 4th gen intake flows more than enough, and the aftermarket intakes are well known for losing low end torque.
Any internal mods or just bolted?
No aftermarket setup has any gains over stock air box. Unless your cammed and tuned, the stock 4th gen intake flows more than enough, and the aftermarket intakes are well known for losing low end torque.
Any internal mods or just bolted?
Last edited by asand1; Oct 12, 2012 at 09:45 PM.
Junior Member
Joined: Oct 2012
Posts: 67
From: New York
But even before I got the cams installed, both Injen and FWI had noticible gains, dyno said so too, im not lying.
On this forum ive read in multiple threads that the stock intake is better than all aftermarket ones. How is this true? Did you guys even run a dyno test or is this just some 'maxima.org rumor'. I noticed that a lot of mods are frowned upon here, whats up with that?
If your max is completely bone stock EXCEPT for an aftermarket intake, then yeah maybe youl lose power, but all bolt-ons are meant to work together. Intake + exhaust + cams + flywheel + udp + ecu + whatever else will def give you gains. I would never run the stock airbox with all those mods.
Last edited by Venix; Oct 13, 2012 at 01:39 AM.
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Listen and read and you will learn. (2 ears, 2 eyes, 1 voice)
#1 Smoothing the shape will help minimize turbulence that could decrease air-flow to the inlet snorkel.
#2 On the 5th Gen there's a beveled area on the rad support that guides air into the snorkel. I'm concerned that the bend & attachment of the plate to the bottom of your snorkel, may block the area &/or cause turbulence, decreasing air-flow. Attaching the plate to the front of the rad support below the bevel keeps that area open.
#3 On the 5th Gen there's a definite curve shaped open area on the underside of the hood contoured to match the area above the snorkel. There's no gasket in this area it's wide open, to help guide air-flow into the snorkel. I'm concerned your 'hood' over the snorkel may block the under-hood opening &/or cause turbulence, decreasing air-flow.
#4 It looks like the plate is made from metal, which will conduct under-hood heat & heat-soak at low speed/stopped. Plastic is much better at preventing heat-soak. In fact my 5th Gen "CAD" design is more effective at lowering IAT in low speed/stopped conditions than at higher speeds.
Well, let's not turn this into another one of these darn which is better threads like has happened endlessly.
I did research on here and saw a post from years ago where they did a dyno test between the CAI and stock and the stock did better "overall" and especially on the low end but not as much on the high end, all I'm giving is a different way to direct that cold air up the the stock inlet for those people that like the advantages that the stock intake gives but would like it to breathe just a little better on the high end.
I did research on here and saw a post from years ago where they did a dyno test between the CAI and stock and the stock did better "overall" and especially on the low end but not as much on the high end, all I'm giving is a different way to direct that cold air up the the stock inlet for those people that like the advantages that the stock intake gives but would like it to breathe just a little better on the high end.
The only modification I did was remove the resonator that connects to the inlet snorkel
Last edited by Shift_A32B; Oct 13, 2012 at 11:00 AM.
First off I want to say nice work! Since I designed/implemented the original 5th Gen "CAD"(Cool Air Diverter) mod. It's gratifying to see an adaptation of the concept on a 4th Gen. That said, I'd like to offer some insight that may help improve your design.
#1 Smoothing the shape will help minimize turbulence that could decrease air-flow to the inlet snorkel.
#2 On the 5th Gen there's a beveled area on the rad support that guides air into the snorkel. I'm concerned that the bend & attachment of the plate to the bottom of your snorkel, may block the area &/or cause turbulence, decreasing air-flow. Attaching the plate to the front of the rad support below the bevel keeps that area open.
#3 On the 5th Gen there's a definite curve shaped open area on the underside of the hood contoured to match the area above the snorkel. There's no gasket in this area it's wide open, to help guide air-flow into the snorkel. I'm concerned your 'hood' over the snorkel may block the under-hood opening &/or cause turbulence, decreasing air-flow.
#4 It looks like the plate is made from metal, which will conduct under-hood heat & heat-soak at low speed/stopped. Plastic is much better at preventing heat-soak. In fact my 5th Gen "CAD" design is more effective at lowering IAT in low speed/stopped conditions than at higher speeds.
#1 Smoothing the shape will help minimize turbulence that could decrease air-flow to the inlet snorkel.
#2 On the 5th Gen there's a beveled area on the rad support that guides air into the snorkel. I'm concerned that the bend & attachment of the plate to the bottom of your snorkel, may block the area &/or cause turbulence, decreasing air-flow. Attaching the plate to the front of the rad support below the bevel keeps that area open.
#3 On the 5th Gen there's a definite curve shaped open area on the underside of the hood contoured to match the area above the snorkel. There's no gasket in this area it's wide open, to help guide air-flow into the snorkel. I'm concerned your 'hood' over the snorkel may block the under-hood opening &/or cause turbulence, decreasing air-flow.
#4 It looks like the plate is made from metal, which will conduct under-hood heat & heat-soak at low speed/stopped. Plastic is much better at preventing heat-soak. In fact my 5th Gen "CAD" design is more effective at lowering IAT in low speed/stopped conditions than at higher speeds.
Thanks for your insight, it's still in it's rough stage.
Their is a definite difference between the two models and Nissan must have learned and adapted for the 5th gen., the 4th gen does not have the beveled area on the radiator support, it's just a hard edge and it goes straight across.
I'm not sure if my pics. show it well, but I rolled the leading edge that goes up to the intake inlet so that the air may flow more smoothly over the top, i doubt that the 1/8" edge to the inlet of the snorkel actually causing any turbulence because the air being forced upward from the plate would shove it up into the hood where the poor bends I currently have would be more the issue at hand.
I'll be fixing those in the near future by filling, shaping, and smoothing the shape to better guide the air flow into the snorkel. I may go ahead and lay down a thin layer in front of the snorkel edge though to help quell any possible turbulence by smoothing out that rounded edge more and then lifting up to a better transition into the snorkel inlet.
As far as the plate being made of metal, I have felt the thing after hours of driving and it's completely cool to the touch, it gets constant cooling by being in the air flow, up front, constantly and has no direct contact with a heat source significant enough to cause heat transition to occur.
The radiator of course will get quite hot, as we all know, but the radiator is held away from the support and itself does not carry the heat over.
Your plastic scoop works nicely on the 5th gen since it stops right before the bevel, for us it would stop short and leave a hard 90 degree turn into the inlet...if it could get past the hood being in the way, which in the 4th gen, it can not....not easily or efficiently at least.
My scoop was shaped with those hard cuts on the sides to actually match up to the shape of the hood and help keep the air funneled up to the snorkel, I plan on filing the edges down to make them more smooth and attractive...tin sheers are not the easiest tool to work cleanly cuts, they have a tendency to not cut at times and then bend the metal as it cuts, but they are way faster than using a dremel, which is probably how i'll sand down some of the hard corners and edges.
It's still a work in progress and I will update with more pics as I finish stage two.
First off I want to say nice work! Since I designed/implemented the original 5th Gen "CAD"(Cool Air Diverter) mod. It's gratifying to see an adaptation of the concept on a 4th Gen. That said, I'd like to offer some insight that may help improve your design.
#1 Smoothing the shape will help minimize turbulence that could decrease air-flow to the inlet snorkel.
#2 On the 5th Gen there's a beveled area on the rad support that guides air into the snorkel. I'm concerned that the bend & attachment of the plate to the bottom of your snorkel, may block the area &/or cause turbulence, decreasing air-flow. Attaching the plate to the front of the rad support below the bevel keeps that area open.
#3 On the 5th Gen there's a definite curve shaped open area on the underside of the hood contoured to match the area above the snorkel. There's no gasket in this area it's wide open, to help guide air-flow into the snorkel. I'm concerned your 'hood' over the snorkel may block the under-hood opening &/or cause turbulence, decreasing air-flow.
#4 It looks like the plate is made from metal, which will conduct under-hood heat & heat-soak at low speed/stopped. Plastic is much better at preventing heat-soak. In fact my 5th Gen "CAD" design is more effective at lowering IAT in low speed/stopped conditions than at higher speeds.
#1 Smoothing the shape will help minimize turbulence that could decrease air-flow to the inlet snorkel.
#2 On the 5th Gen there's a beveled area on the rad support that guides air into the snorkel. I'm concerned that the bend & attachment of the plate to the bottom of your snorkel, may block the area &/or cause turbulence, decreasing air-flow. Attaching the plate to the front of the rad support below the bevel keeps that area open.
#3 On the 5th Gen there's a definite curve shaped open area on the underside of the hood contoured to match the area above the snorkel. There's no gasket in this area it's wide open, to help guide air-flow into the snorkel. I'm concerned your 'hood' over the snorkel may block the under-hood opening &/or cause turbulence, decreasing air-flow.
#4 It looks like the plate is made from metal, which will conduct under-hood heat & heat-soak at low speed/stopped. Plastic is much better at preventing heat-soak. In fact my 5th Gen "CAD" design is more effective at lowering IAT in low speed/stopped conditions than at higher speeds.
Anyway, I appreciate your reply and ideas.
Their is a definite difference between the 4th and 5th gens. that shows Nissan caught on and changed the design for better airflow.
The 5th gen has a better shaped hood where the 4th gen completely blocks the air inlet off. The 5th gen also has a bevel in the radiator support to help guide the air up, the 4th gen just has a hard 90degree turn which is just the edge of the radiator support and it goes right up to the back edge of the hood, which helps get air to the radiator, but nothing is given to the air intake area.
My design is still rough and i'll be shaping that underhood sadness much more in the future, making the air flow much smoother and better guided.
The metal does not touch any direct heat source and is cool to the touch even after hours of driving as it is constantly cooled by being in the cool air out front and it doesn't make any contact with the radiator, the support doesn't carrry enough heat to bother it.
I'll be puttying and shaping certain areas to improve the transition into the inlet in the future and I will post up some more pics. as it improves in design.
I don't know if the pictures show it but I rolled the top edge to help it guide the air over that hard edge of the radiator support, i'll smooth that transition a little better as well.
Thanks..glad ya chimed in.
Tom
My first clue was the poorly shutting passenger front door that I thought just had a bad hinge only to find that the beam that holds the door hinges
is bent on the lower half and the sill is knocked in flat and has a bunch of putty that was painted over, the door is off of a different car (has a different VIN#)
The paint on the right front fender is obviously new as is the bumper and hood.
My radiator support doesn't have it which makes me wonder if the Chinese missed adding that in when the part was made..
Either way, this has been an effective mod. and I'm glad I did it. Now to just finish it nicely so it doesn't look like such a hack job.
An air dam has to stop air from getting out again and it can just circulate in there. Also there is no way for the air to make a 90 degree turn and go into the OEM scoop. Its a good idea and worth toying around with but this one will not yield any more air flow. Trust me. I know the stock intake very well and have modified it countless times including making a scoop that connects to the bottom of the OEM scoop where another box connects, the circular connection
Junior Member
Joined: Oct 2012
Posts: 67
From: New York
Can someone tell me exactly HOW Injen is the so-called worst of them all, and HOW stock is the so-called best?
Thru testing, these are my results...
1: Injen & PR dynoed mid to high torque & hp gains, slight gains down low.
2: Short ram dynoed slight gains all around.
3: Stock was about the same down low, and did HORRIBLE past 4500rpm.
Our intake manifold robs power passed 5000rpm, and the stock airbox just made things even worse up high.
Injen and PR are exactly the same and dynoed exactly the same. The pipes are the same length. If its a hot day, then there is NO COLD AIR TO BEGIN WITH, so how can 1 get colder air than the other? They both have the same concept, long pipe and more air: 2 effective traits.
Once again, Im going by a dyno session from 2 years ago, car was a 98 i30t 5MT.
Now can someone please give me their reason WHY the information here is opposite mine? Nobody is explaining, only saying what they think is the best.
Last edited by Venix; Oct 17, 2012 at 06:52 PM.
Place racing and Injen had the same gains on my dyno sheet, same growl too.
Can someone tell me exactly HOW Injen is the so-called worst of them all, and HOW stock is the so-called best?
Thru testing, these are my results...
1: Injen & PR dynoed mid to high torque & hp gains, slight gains down low.
2: Short ram dynoed slight gains all around.
3: Stock was about the same down low, and did HORRIBLE past 4500rpm.
Our intake manifold robs power passed 5000rpm, and the stock airbox just made things even worse up high.
Injen and PR are exactly the same and dynoed exactly the same. The pipes are the same length. If its a hot day, then there is NO COLD AIR TO BEGIN WITH, so how can 1 get colder air than the other? They both have the same concept, long pipe and more air: 2 effective traits.
Once again, Im going by a dyno session from 2 years ago, car was a 98 i30t 5MT.
Now can someone please give me their reason WHY the information here is opposite mine? Nobody is explaining, only saying what they think is the best.
Can someone tell me exactly HOW Injen is the so-called worst of them all, and HOW stock is the so-called best?
Thru testing, these are my results...
1: Injen & PR dynoed mid to high torque & hp gains, slight gains down low.
2: Short ram dynoed slight gains all around.
3: Stock was about the same down low, and did HORRIBLE past 4500rpm.
Our intake manifold robs power passed 5000rpm, and the stock airbox just made things even worse up high.
Injen and PR are exactly the same and dynoed exactly the same. The pipes are the same length. If its a hot day, then there is NO COLD AIR TO BEGIN WITH, so how can 1 get colder air than the other? They both have the same concept, long pipe and more air: 2 effective traits.
Once again, Im going by a dyno session from 2 years ago, car was a 98 i30t 5MT.
Now can someone please give me their reason WHY the information here is opposite mine? Nobody is explaining, only saying what they think is the best.
Aackshun and I were going to dyno the short ram(Bomz) vs the stock intake but sadly it never happened due to time. Modern day intake systems designed by the manufacturers are the best you can get as far as performance. Gains can still be made in the filter medium however. Our car is old so it might not be as well designed as say, a 2012 car, but it is still engineered far more than Injen or any other brand did. The only thing wrong with the stock intake is the method of air delivery. It suffers as demand for air increases at higher RPMS.
Aackshun and I were going to dyno the short ram(Bomz) vs the stock intake but sadly it never happened due to time. Modern day intake systems designed by the manufacturers are the best you can get as far as performance. Gains can still be made in the filter medium however. Our car is old so it might not be as well designed as say, a 2012 car, but it is still engineered far more than Injen or any other brand did. The only thing wrong with the stock intake is the method of air delivery. It suffers as demand for air increases at higher RPMS.
I wouldn't knock the oldness of the VQ too hard. It was an extremely well designed motor. Look at any NA 3.0 engine by any manufacturer. Do they make significantly more power, if at all? Also, fact is, Nissan could only improve its VQ power by increasing displacement and making the cylinder head more VTECy. Power improved with significantly increased complexity. Direct injection was supposed to finally be the be-all end all, but manufacturers are still struggling with it due to emissions. Nissan, interestingly, did not need to resort to direct injection (yet)
..... Still waiting... I am very interested in this as i have a PR knock off intake ready to replace the SRI that came on my car. I am sure I will have gains over SRI but am still curious how both compare to the stocker. I find it hard to believe that the Oem air box would be the better option but i cannot say since i never had one.
Now before you blast me too badly just check out what I did and I think it makes perfect sense.
I had recently re-installed my stock intake and love the way it pulls nicer from a stop, but didn't like the way it falls flat after that.
I've looked at all kinds of posts about this nonsense and saw the graphs on stock vs. cai and saw what little difference their is overall, but it's a definite and obvious thing the way it doesn't pull hard enough, too me it just seemed to not be getting enough air.
So I popped the hood and studied the inlet and hood design, then closed it to the first click of the latch and then looked at it. The damn hood pretty much completely blocks off air going into the inlet so how could it possibly get enough air when it requires "more".
Ding! (that was the light bulb going on in my head) why not push some air up to the inlet via a different but not obvious way...but cheaply.
Here was my idea...now nevermind the crafty-ness of the work as this was all just a trial to see if my idea made any viable results...well it did.
You can definitely feel the better pull from the mid range and up, and best of all it was relatively easy and cheap.
I wanted to make a plate that would route air up to the intake from the front but not be obvious or ugly about it, the best route was from the smaller upper grille (i have a '96), I looked behind the grille and saw that their was a logical route to use up to the intake inlet on the right side, I just had to shape a plate the right way as too get around the hood latch and not cut my stupid finger every time I reached for it, but still force air up to the inlet.
I got a piece of paper and folded it around a bit to get my rough idea, then transferred it to cardboard where I taped together my basic model. Once I got the right layout I cut the tape holding the sides and folded the design out flat onto a thin and bendable/cuttable sheet of aluminum and drew some fold lines with a marker where I needed to fold the sides, bottom, and top.
Here is a pic. of this idea, it's basically a "ram air" set up as it basically takes air and shoves it up to the intake.
Here you can see I just utilized the stock screws to hold it on the lower end and then just used the fasteners for the plastic inlet to hold the scoop in place on the top and made the scoop with enough extra length to go over the top of the radiator support and then bend the metal around the back to help hold it solidly in place.
This left one thing to do. If you look at the hood when it's open to only one click of the latch you can see just how much the hood blocks the air.
I needed to shape the hood to allow the air from the scoop to pass and be guided into the air inlet.
I know it needs to be cleaned up and looks awfully rough, but it was a test bed and I didn't care since nobody was going to see it unless I pointed it out.
I used some tin snips and cut a line across and then two vertical cuts, one on each side, then used a hammer to knock the metal in and form it better to help guide the air.
Like I said, this is pretty rough, first round stuff. I'll be throwing a little body putty on their and cleaning it up later, this was just to do the basics and spray over it to keep it from rusting.
Here you can see the formed hood over top of the scoop, the view makes it look a little out of whack, but it lines up.
I know this is a little unorthodox perhaps, but it just seemed to make sense and after doing a couple different searches I didn't come up with anything that was like this, I saw hybrids and hacked up boxes, but that seemed to me like any air from inside the engine bay would still be warm and if you were getting any air from the inlet pipe it was going right out the big hole instead of forcing it's way up through the filter to the throttle body.
Now some of you may have concerns about blocking off half the grille, I can tell you that I have not seen the temperature needle budge one bit as the radiator is fed air from the massive hole we have in our front bumper alot more than this small grille up top.
Water may also be an issue, as in "rain". I drove it home for 2 1/2 hours from my girlfriends house to work, in a heavy rain, and checked it when I got back home and under the carport.
Their was a little bit of water streaking at the top of the scoop, so I pulled the plug i installed (at the port where the elbow used to go down under the battery) and it was totally dry. I then opened up the filter box and checked down in the bottom of the box, under the filter, again...totally dry.
Let me know what you guys think....I know you will anyway.
Like it or don't...it's their and it works. I've noted a nice pull all the way 'til it cuts out at the limiter now, it definitely didn't pull this nice before and seems to have done the trick nicely.
Best part, I painted it black and you can't even see it from the front with the hood closed and theirs no loud intake noise, just smooth usable power.
I had recently re-installed my stock intake and love the way it pulls nicer from a stop, but didn't like the way it falls flat after that.
I've looked at all kinds of posts about this nonsense and saw the graphs on stock vs. cai and saw what little difference their is overall, but it's a definite and obvious thing the way it doesn't pull hard enough, too me it just seemed to not be getting enough air.
So I popped the hood and studied the inlet and hood design, then closed it to the first click of the latch and then looked at it. The damn hood pretty much completely blocks off air going into the inlet so how could it possibly get enough air when it requires "more".
Ding! (that was the light bulb going on in my head) why not push some air up to the inlet via a different but not obvious way...but cheaply.
Here was my idea...now nevermind the crafty-ness of the work as this was all just a trial to see if my idea made any viable results...well it did.
You can definitely feel the better pull from the mid range and up, and best of all it was relatively easy and cheap.
I wanted to make a plate that would route air up to the intake from the front but not be obvious or ugly about it, the best route was from the smaller upper grille (i have a '96), I looked behind the grille and saw that their was a logical route to use up to the intake inlet on the right side, I just had to shape a plate the right way as too get around the hood latch and not cut my stupid finger every time I reached for it, but still force air up to the inlet.
I got a piece of paper and folded it around a bit to get my rough idea, then transferred it to cardboard where I taped together my basic model. Once I got the right layout I cut the tape holding the sides and folded the design out flat onto a thin and bendable/cuttable sheet of aluminum and drew some fold lines with a marker where I needed to fold the sides, bottom, and top.
Here is a pic. of this idea, it's basically a "ram air" set up as it basically takes air and shoves it up to the intake.
Here you can see I just utilized the stock screws to hold it on the lower end and then just used the fasteners for the plastic inlet to hold the scoop in place on the top and made the scoop with enough extra length to go over the top of the radiator support and then bend the metal around the back to help hold it solidly in place.
This left one thing to do. If you look at the hood when it's open to only one click of the latch you can see just how much the hood blocks the air.
I needed to shape the hood to allow the air from the scoop to pass and be guided into the air inlet.
I know it needs to be cleaned up and looks awfully rough, but it was a test bed and I didn't care since nobody was going to see it unless I pointed it out.
I used some tin snips and cut a line across and then two vertical cuts, one on each side, then used a hammer to knock the metal in and form it better to help guide the air.
Like I said, this is pretty rough, first round stuff. I'll be throwing a little body putty on their and cleaning it up later, this was just to do the basics and spray over it to keep it from rusting.
Here you can see the formed hood over top of the scoop, the view makes it look a little out of whack, but it lines up.
I know this is a little unorthodox perhaps, but it just seemed to make sense and after doing a couple different searches I didn't come up with anything that was like this, I saw hybrids and hacked up boxes, but that seemed to me like any air from inside the engine bay would still be warm and if you were getting any air from the inlet pipe it was going right out the big hole instead of forcing it's way up through the filter to the throttle body.
Now some of you may have concerns about blocking off half the grille, I can tell you that I have not seen the temperature needle budge one bit as the radiator is fed air from the massive hole we have in our front bumper alot more than this small grille up top.
Water may also be an issue, as in "rain". I drove it home for 2 1/2 hours from my girlfriends house to work, in a heavy rain, and checked it when I got back home and under the carport.
Their was a little bit of water streaking at the top of the scoop, so I pulled the plug i installed (at the port where the elbow used to go down under the battery) and it was totally dry. I then opened up the filter box and checked down in the bottom of the box, under the filter, again...totally dry.
Let me know what you guys think....I know you will anyway.
Like it or don't...it's their and it works. I've noted a nice pull all the way 'til it cuts out at the limiter now, it definitely didn't pull this nice before and seems to have done the trick nicely.
Best part, I painted it black and you can't even see it from the front with the hood closed and theirs no loud intake noise, just smooth usable power.